Body weight independently affects articular cartilage catabolism.

Although obesity is associated with osteoarthritis, it is unclear whether body weight (BW) independently affects articular cartilage catabolism (i.e., independent from physiological factors that also accompany obesity). The primary purpose of this study was to evaluate the independent effect of BW on articular cartilage catabolism associated with walking. A secondary purpose was to determine how decreased BW influenced cardiovascular response due to walking. Twelve able-bodied subjects walked for 30 minutes on a lower-body positive pressure treadmill during three sessions: control (unadjusted BW), +40%BW, and -40%BW. Serum cartilage oligomeric matrix protein (COMP) was measured immediately before (baseline) and after, and 15 and 30 minutes after the walk. Heart rate (HR) and rate of perceived exertion (RPE) were measured every three minutes during the walk. Relative to baseline, average serum COMP concentration was 13% and 5% greater immediately after and 15 minutes after the walk. Immediately after the walk, serum COMP concentration was 14% greater for the +40%BW session than for the -40%BW session. HR and RPE were greater for the +40%BW session than for the other two sessions, but did not differ between the control and -40%BW sessions. BW independently influences acute articular cartilage catabolism and cardiovascular response due to walking: as BW increases, so does acute articular cartilage catabolism and cardiovascular response. These results indicate that lower-body positive pressure walking may benefit certain individuals by reducing acute articular cartilage catabolism, due to walking, while maintaining cardiovascular response. Key pointsWalking for 30 minutes with adjustments in body weight (normal body weight, +40% and -40% body weight) significantly influences articular cartilage catabolism, measured via serum COMP concentration.Compared to baseline levels, walking with +40% body weight and normal body weight both elicited significant increases in articular cartilage catabolism, while walking with -40% body weight did not.Cardiovascular response (HR and RPE) was not significantly different during walking with normal body weight and when compared to walking with -40% body weight.

Planning for Happenstance: Helping Students Optimize Unexpected Career Developments.

Introduction: Planning for and responding to happenstance is an important but rarely discussed part of the professional development of medical students. We noted this gap while conducting a study of career inflection points of 24 physicians who frequently mentioned how luck had shaped their unfolding careers. A review of the career counseling literature led us to a body of work known as Planned Happenstance Learning Theory (PHLT). PHLT focuses on the attitudes and skills to make happenstance a positive force in one's life. We found no reference to this work in the medical education literature and resolved to address this gap. Methods: We created resources for an interactive, 90-minute faculty development workshop. In the workshop, the facilitator used a PowerPoint presentation, vignettes of happenstance, a student testimonial, and a reflection worksheet. We presented and formally evaluated the workshop at three national meetings for health science educators. Results: Workshop participants, mostly faculty (N = 45), consistently expressed positive regard for the workshop content, organization, and instructional methods, especially the opportunity for guided reflection. A retrospective pre/postevaluation revealed a meaningful increase in knowledge about PHLT attitudes and skills, as well as a commitment to use these skills in promoting professional development. Discussion: The skills and attitudes of PHLT are relevant to students' career development. A workshop designed to introduce PHLT skills and attitudes to faculty advisors and mentors can help prepare faculty to promote students' awareness and use of these attitudes and skills.

Case of relapsing sulfasalazine-induced hypersensitivity syndrome upon re-exposure.

Sulfasalazine-induced hypersensitivity syndrome (SIHS) is a serious systemic delayed adverse drug reaction that is associated with significant morbidity and mortality. Here, we report the first case, to our knowledge, of a patient with previously unidentified SIHS who developed a significantly more rapid and extreme recurrence on re-exposure to sulfasalazine. The patient is a 58-year-old woman with asymptomatic Crohn's disease who, 10 days after initiating sulfasalazine, developed fevers, diffuse rash, pancytopenia, hypotension and hepatitis without a definitive source of infection. Sixteen days after her first hospitalisation, she was restarted on sulfasalazine and was readmitted within 10 hours with a similar but more serious presentation, requiring vasopressors. She did recover completely without any further recurrence to date, after definitively discontinuing sulfasalazine. This case demonstrates the importance of recognising SIHS early in patients to prevent re-exposure to sulfasalazine and to ensure timely initiation of appropriate treatment.

Ambulation speed and corresponding mechanics are associated with changes in serum cartilage oligomeric matrix protein.

Because serum cartilage oligomeric matrix protein (COMP) has been used to reflect articular cartilage condition, we aimed to identify walking and running mechanics that are associated with changes in serum COMP. Eighteen subjects (9 male, 9 female; age=23 ± 2 yrs.; mass=68.3 ± 9.6 kg; height=1.70 ± 0.08 m) completed 4000 steps on an instrumented treadmill on three separate days. Each day corresponded to a different ambulation speed: slow (preferred walking speed), medium (+50% of slow), and fast (+100% of slow). Synchronized ground reaction force and video data were collected to evaluate walking mechanics. Blood samples were collected pre-, post-, 30-minute post-, and 60-minute post-ambulation to determine serum COMP concentration at these times. Serum COMP increased 29%, 18%, and 5% immediately post ambulation for the fast, medium, and slow sessions (p<0.01). When the speeds were pooled, peak ankle inversion, knee extension, knee abduction, hip flexion, hip extension, and hip abduction moment, and knee flexion angle at impact explained 61.4% of total variance in COMP concentration change (p<0.001). These results indicate that (1) certain joint mechanics are associated with acute change in serum COMP due to ambulation, and (2) increased ambulation speed increases serum COMP concentration.